LeatherLyke ?

well, i was hasty;  leatherlykes do paint-up ok.  used "rustoelum plastic primer and paints.  seems to be holding up ok.  had to use numerous coats.  not a painter, so it looks kinda sick close-up but looks ok from about 10 feet

By that time and expense, you might consider buying new bags.

Obviously, you can get decent bags anywhere from $150-650.

If your friend can re-cover bags in leather or synth at a decent price, we might be able to throw some business his way.

[Roger]

Recently I found that Mother's Back-to-Black seems to work very well.  Only been in the rain once since I tried it, I wiped off the water at the end of the ride and, low & behold, no gray rain spots or water marks.

[Pistolchamp]

I never thought about it.  Yes, they get a bit dull after a rainy ride, but, I just wipe them with ArmorAll and they look great.  2003 standard with 47,000 miles and the bags came with the bike new.  No complaints about the bags, they carry what I want and look nice when cleaned up as above.