Having decals made is a very expensive undertaking. I just cut my numbers out of trim sheet. I cut the number out of black trim sheet and stick it on to red trim sheet then cut the number out again 1/16th bigger. That gives me a pinstripe that won't come off. Then I stick it on the plane using the "soapy suds" method. I use a straight edge and X-acto knife and scissors. The only curved line in the whole thing is in the "R". It's pretty easy.

Adrian