A good friend who has been collecting wine and port for some time explained to me a few years ago that Vintage Port prices track the stock market very well. When the market is down, load up on vintage port; when it is up, drink what you have loaded up on.
The market has been up, so avoid it.
Still, you might want to keep an eye on what Sam's and The Chicago Wine Company have on offer. In the auction last week, tcwc (
www.tcwc.com) had some very nice vintage ports on offer with an estimate of between $20 and $40 - above your range, sure, but you may want to splurge sometime and might even find a good $20 bottle. They also sell stuff outright, but the lowest priced vintage port looks to be about $35 right now.
Have you considered some other sweet wines - say Tokaji from Hungary, or maybe Sherry or some of the more obscure dessert wines from the south of France? Flavor profiles differ greatly, but so long as you avoid Sauternes, most of these will cost much less than Port (Tokaji being the one possible exception) and you may find something you like.
Sam's may let you sample some Sherries or some Tokaji if you hit them on the right day.
d
Feeling (south) loopy