I have a longbow with very streaked clear glass over purpleheart limbs. I was thinking about painting the bows back and belly purple then polying over. Can this be done?

I have used Acrylic paint you get at wal-ma--
and it works fine.
It will wipe off with water and a rag.
It will scratch easy until you get it polyed

Krylon spray paint comes in lots of colors and should work.

Several years ago I had a set of limbs with very streaky glass.  I sanded the glass just like I was going to put on finish, but sprayed with Krylon paint then finished as usual.  They have held up  great and still look good.  I only wished I would have picked a color resembling the glass of days long gone by.