Best budget spare setSheetsAmazon Basics
Amazon Basics Brushed Microfiber 4-Piece Sheet Set (Queen, Dark Gray)
Brushed microfiber 4-piece sheet set with 14 inch pockets
LANE LINEN 450TC Long-Staple Cotton Sateen Sheet Set (Queen, White)

Best cotton sateen for the money
LANE LINEN $$$
450TC long-staple cotton sateen set with 15 inch pockets
LANE LINEN's 450TC set is 100% long-staple cotton sateen with a 15 inch deep-pocket fitted sheet, OEKO-TEX Standard 100 certified.
Who it's for: Anyone moving from microfiber to cotton.
Skip if: You want the coolest possible sheets.
Alternatives with different tradeoffs — not clones of the same pitch.
Best budget spare setSheetsAmazon Basics
Brushed microfiber 4-piece sheet set with 14 inch pockets
Best cooling sheetsCoolingBedsure
Silky rayon-from-bamboo 4-piece sheet set