depends on what you see as "affordable". everyone's budget is different, therefore, everyone's "affordable" is different. smartpak has good ones that are $200 or less. my favorite, rather inexpensive jacket, is the grand prix jackets ($400 or less) & the rj classics ($500 or less). however, i highly recommend investing in a nice jacket. . .i show in a custom charles ancona and absolutely loveee it!
Any Kerrits jacket because I got a pretty blue one for 130 dollars
Tuff rider and smartpak have good ones