This post may contain an affiliate link that helps support GBFans.com when you make a purchase at no additional cost to you.Sometimes a long shot, but you might get lucky on eBay for the body and the probe base...
I put this entire thing together for about $150 total...
Bacharach Sniffer 302 body from eBay, the probe base I got from a Bacharach Sniffer 503A on eBay (if you're scavenging parts, make sure it comes with the probe), the copper tube is from Amazon (
http://smile.amazon.com/gp/product/B003JU31EK), the aspirator hose is also from Amazon (
http://smile.amazon.com/gp/product/B004CR4OSG), and then the aspirator is just some random aspirator I found on eBay that looked similar to the original...
By the way, the probe base has an inner thread of 1/4-28, so you may need to find a way to thread the copper tube on... I used a threaded rod from Amazon (
http://smile.amazon.com/gp/product/B000FOYLCO), but that may be overkill, really... You can probably find a cheaper option at your local hardware store...