This is no longer a hard problem to solve. . .
First of all, I wouldn't worry about "permission".
1) If there is nobody to ask, there is also nobody to complain.
2) The usual remedy for copyright infringment is a cease and desist letter.
3) If you're recreating the logo to put back on your own Sunline that would consistute restoration which I believe is a "fair use"
4) Even if you're creating and reselling decals I doubt you'd have a problem.
Second - there are now companies on the internet that will make decals.
Custom Stickers, Die Cut Stickers and Laptop Skins - Sticker Mule
is just one example. They will make waterproof, fade resistant, 6mil decals up to 6ft by 6ft for as little as $44 per 100.
They will also "fix" low resolution art work for free.
Stoltzfus should be shot for trying to charge $50 for something they probably got from the factory for free when it shut down.
I don't have time right now to deal with getting new Logos made form my 1950 but when I do, I'll make the other 49 available here for a lot less than $50 - say $49.95? LOL.
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