I have fun with borders, as you can see from these:
http://www.cartographersguild.com/showthread.php?t=6673
http://www.cartographersguild.com/showthread.php?t=6590


What' i would suggest though, is look through the thumbnail collection here:
http://www.cartographersguild.com/ut...nishedMaps.htm

There's a lot of maps with no borders, but if you skim through there you may find a few you like, then follow to the thread and check with the original author

Other than that, what I typically do is head over to google images, and type in "antique maps" or something similar and see what catches my eye.