I have done alot of looking for -17 stuff in 48 scale. your decal choices are limited. I finally decided to do mine in an actual bomb squadron, but a fictional airplanee, and hand paint the nose art (gonna name it after my daughter)
as for after market stuff, go to squadron.com, they have all the cool aftermarket stuff. I just got my wheels and cockpit sets #1 and #2, and the walk around book. i think it came up to about $40.00 for that stuff. the photo etch stuff from virlidin is about $20.00 a set, they have three at squadron, and the upgrade kit is about $32.00.
i hope you enjoy the kit, i just started fiddling with mine today and have found a few things that confuse me, and im a bit nervous too (first time scratch building and cutting up a $40.00 kit...oh well guess i have to learn sometime
enjoy, and hope this helped
jim