There are many good products out there and, in use, we usually stop when we find a product that gives us good performance. By my measure, the one that I am currently stuck on, is Black-Rock. Bing or Google for best source. It's not cheap but it is good. I use it on "vintage" leather as in your application. ....
A little goes a long way.
"vintage" (A Progressive's word for old !! )
http://www.pfiwestern.com/pfi/wester...tml?item=BLR01
Good luck and;
Be Safe !!!