Re: Starcraft Jet Star 15 Restore
$170 w/ upholstery isn't too bad, unless there are NO close matches for the rest of the interior.
GreatLakeSkipper has blown up diagrams of seats, that might work as plans, depending on what size your after. If they aren't the right dimensions, you could probably figure out what would work & go from there.
All in for hinges, vinyl, plywood, foam legs/braces/hinges for the fold out position would be a good bit of $170:
3 16" piano hinges per set
1/2 sheet 4X8 3/8" plywood for seats & backs per set
free couch foam cushions w & spray adhesive
vinyl $7-10/yd on sale (3-4yrds per set)
glue, screws, staples, spar for assembly & sealing
1/2 sheet 4X8 1/2" ply for base
unless you already have the pieces, just need to know how to put them together.