A couple of thoughts. First, if you can't source them locally, you can get an inexpensive 27" wheelset from Harris Cyclery, around $100 on up to $160 or so: http://sheldonbrown.com/harris/wheels/630.html

Second, consider getting some Schwalbe Marathons. They still make them in 27 x 1.25 size. I needed to adjust out my fenders for them because they are noticeably larger than my prior 27" tires (Panaracers or Kenda). The Schwalbes have proven to be very tough. Again, Harris has a nice selection of the Schwalbes and other 27" tires if you can't source them locally: http://sheldonbrown.com/harris/tires/630.html

One other option is to get a custom wheelset built by someone like Peter White. I bought a set of 27" wheels from him recently -- Sun CR-18 rims and Shimano Tiagra hubs -- for around $270 plus shipping. They look great and no problems thus far.

Finally, will your bike work with 700c wheels? I have to stick with 27" due to the cantilever brake bosses, but maybe your brakes will allow use of the slightly smaller (and much more available) 700c wheels.