This link at least gives you some info to consider...... {No offense to vstech, just his link source}

http://www.***************/search/product.aspx?sid=4dd3pq45cy2ivq551rfizi45&makeid=800016@Mercedes&modelid=1192946@240D&year=1977&cid=24@AC%20%26%20Heat%20-%20Climate%20Control&gid=6628@AC%20Compressor

and

http://cgi.ebay.com/ebaymotors/Air-Conditioning-Compressor-York-Style-TubeO-WithClutch_W0QQitemZ170102482607QQihZ007QQcategoryZ33543QQrdZ1QQcmdZViewItem

even better...

http://cgi.ebay.com/ebaymotors/MERCEDES-114-115-EARLY-123-YORK-A-C-COMPRESSOR_W0QQitemZ270111220716QQihZ017QQcategoryZ6763QQrdZ1QQcmdZViewItem

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John