The real problem at hand here is that you need graphics cut for these, and need files to have Nick cut/print them. This means you need vector or high resolution raster graphics. EPS file format doesnt really mean shit, as it can be an EPS and still be low res raster.
It is likely impossible that you will find vector images for these, and unlikely that you will find raster images with enough resolution.
It is pointless to have someone “convert” a JPG/GIF/(any raster) image into an EPS, since it will still just be a low resolution file with an EPS extension.
I think your best bet is to go with one of the kits from the link Jager posted. I know Nick could probably do it cheaper, but without the correct graphic files, it will end up looking terrible.