Here is my limb cutter. Similar but cheaper.
http://www.tractorbynet.com/forums/attachments/141126-hydraulic-limb-snipper.html
http://www.tractorbynet.com/forums/files/power-trac/132460d1239216924t-tree-shear-pt-1445-001-jpg
http://www.tractorbynet.com/forums/files/power-trac/132461d1239217295t-tree-shear-pt-1445-009-jpg
http://www.tractorbynet.com/forums/files/power-trac/52218d1142368280-tree-shear-843650-cutter01-jpg
http://www.tractorbynet.com/forums/files/power-trac/52219d1142369497-tree-shear-843668-cutter02-jpg
http://www.tractorbynet.com/forums/...1d1142371302-tree-shear-843689-sniper-mod-jpg
Total cost about $50. Had most of the parts.
Did you ever work out the hydraulic chainsaw?