Over the last few years, several high-quality stocks have been trading off their highs due to the slowing economy impacting operations and higher interest rates acting as a headwind. Therefore, with interest rates beginning to decline and many hoping the economy will see a soft landing, it's the perfect time for investors to buy these high-quality stocks while they are still on sale.

For many stocks, a slowing economy means fewer sales and lower growth potential, which can hurt their share prices in the near term. Furthermore, in some cases, it can even impact margins.

In addition, higher interest rates not only make it more expensive for companies to service their debt or invest more cash in growing their operations, but they also impact investors' appetites for taking on risk. Plus, as bond yields rise due to higher interest rates, so too do dividend yields, driving the prices of even high-quality and reliable dividend stocks down.

Even with these two significant headwinds subsiding, though, many of the best stocks on the TSX are still on sale, making now an excellent time to buy these stocks to hold for the long haul.

So, if you've got some cash you've been waiting to put to work, here are three of the best stocks to buy now while they are on sale.

One of the best growth stocks in Canada to buy on sale

Despite bouncing back from the lows it reached last year, Aritzia (TSX:ATZ), the ultra-popular women's fashion retailer, continues to remain well off its all-time highs. Therefore, while this impressive growth stock trades cheaply, it's one of the best TSX stocks to buy now.

For years, Aritzia has been rapidly growing its sales, both by opening new stores and through its impressive e-commerce platform. In fact, even with store closures during the pandemic, Aritzia continued to increase its revenue and profitability and has years of growth potential ahead of it as it continues to expand across the U.S.

With the economy slowing down in recent years, though, Aritzia's sales and profitability were temporarily impacted. This led the stock to trade significantly undervalued, which is why it's one of the best stocks to buy today.

Not only is Aritzia expected to grow sales by over 11% this year, but its normalized earnings per share are expected to recover fully from their significant impacts last year.

Therefore, with Aritzia trading at a forward price-to-earnings ratio of just 24.1 times, below its five-year average of 36.5 times, it's certainly one of the best stocks to buy now.

A high-quality industrial real estate stock

Another high-quality Canadian growth stock that's been temporarily impacted by the economic climate is Granite REIT (TSX:GRT.UN).

Granite owns assets like warehouses and distribution centres, which have seen a significant increase in demand in recent years.

With more companies relying on both e-commerce and in-store sales, many have closed some of their brick-and-mortar locations to focus more on e-commerce, leading to an increased demand for warehouse space to store their inventory.

However, in the last couple of years, that growth has unsurprisingly temporarily slowed down, leading to Granite's fall from its highs.

In fact, the stock now trades at a forward price to funds from operations ratio of just 13.9 times, below its five-year average of 17.5 times. In addition, its dividend yield now sits at 4.3%, above its five-year average of 4%.

A top growth stock trading ultra-cheaply

Finally, Cargojet (TSX:CJT) is another stock to buy that's on sale after being temporarily impacted by the economic environment.

Cargojet offers tremendous long-term growth potential as e-commerce continues to gain popularity and the demand for time-sensitive shipping continues to increase.

So, although the worsening economy temporarily impacted e-commerce sales, as those sales rebound and continue to grow well into the future, so too should Cargojet's operations.

Therefore, with sales and earnings expected to rebound sharply this year, Cargojet now trades at a forward enterprise value (EV) to earnings before interest, taxes, depreciation and amortization (EBITDA) ratio of just below 8 times.

That's not only cheap for a high-quality growth stock, but it's also well below its five-year average of 10.6 times. Therefore, while this high-potential growth stock remains on sale, it's easily one of the best stocks to buy today.