what about checking your destination's local bike shops to see if they have bikes for rent? the bike shops around here all rent 21-speed hybrid bikes, which are more or less on par with your 7-speed comfort bike (if less eye-catching than your bike); and at $15/day for rental, it takes all the worry out baggage issues. lastly, you could check craigslist at the location to see if someone could let you use a bike (i see it locally time to time in my area). just some alternate ideas...
very last, if you have the moolah, try a Bike Friday!
http://www.bikefriday.com