I agree, your best bet is to take your decals off and try and salvage them onto a piece of carbboard, and take them to a decal shop and have them make them for you
won't be cheap, but it is possible
they tend to come off rather easy with slow goings and some heat
as for a seat cover?? some custom boat shops I am sure can make you one, but the price might scare you, ,last time I tried to have a boat shop make a colored seat cover, it was like 257+ bucks, they could do it, but I wasn't paying that much LOL
now if you wanted OEM, that would be easier
motodecals.com