Hey there, thank you for asking! Sadly I'm booked full with full-time work at the mo and can't take on any commissions, sorry. :< Were you hoping for the larger versions to still be pixel art, or would 2D art work? Might be easier/cheaper to go for 2D art since high-res pixels could get a little expensive from what I've seen. :D;;
You're also welcome to edit the icons using something like Waifu2x to resize the originals - hopefully something like that could work!