If you're budget-restricted, your best bet is this O'Harrow Pocket Square. It's a wonderful product, while not very pricey. Another strong contender for your wardrobe is this Pocket Square. While the price of this product is rather reasonable, it will definitely attract a lot of attention. You might also want to consider this Asos Pocket Square. The price is very reasonable, but the effect on your wardrobe will be pretty fantastic.
For something in the middle of the price range, consider buying this Eleventy Pocket Square. While the price is very reasonable, this piece is an easy wardrobe update. It's also worth considering this Eleventy Pocket Square. This product is ultra popular and, just as importantly, not very expensive.