According to Racer Walsh's website ( www.racerwalsh.com
) the 2.3 shortblock
weighs in at 185 lbs. for shipping purposes, My best-guess on the cylinder head would be about 50 lbs inluding cam, valves, springs, etc. So roughly 235 lbs. That's the best estimate I can give because the only weight data I could find was the shortblock.
If you just want a rebuilder to rebuild your engine, find a parts store or shop that sells Recon or Jasper rebuilt engines, both are good (Jasper's got a great reputation, and the quality of parts they use is top-notch, I worked in a shop that installed their engines, and I've used two engines from Recon personally and used to sell them professionally.) It'll save you on shipping (most shops/stores have special arrangements with their engine suppliers) and it'll have a warranty.
Doing the work yourself has much to recommend it if you've got the time, tools, a mentor or a good tech book, and the will to do it, as well as access to a good machine shop for any machine work you may need (at least have the block and head vatted and magnafluxed.) The 2.3 would be a great engine to do a first rebuild on, as they're easy to work on, and they are very forgiving of mistakes compared to a lot of other engines out there. (I've even run one with the cam in 180* out when I was 16 and just learning how to do things).