If it's only stained you shouldn't have a problem painting over it.
Any paint should be fine for it being just the stand it's only a problem if the paint can either have water run off it into the tank or be submerged into the tank
So acrylic paints are usually the ones that have that gloss you want tho they are a water based paint (if your worried you can put a coat of clear over that once it's dry) other than that any bathroom paint (tho watch out for anti fungi or anti mold paints) or exterior paints should be OK too.
You will find with most main stream brands of paint the only difference is one will be thinner than the other so the thinner one might need a extra coat of paint with the trade off being drying time between coats (my opinion less coats less effort same results) but just ask in your local hardware store what they recommend is best