Well 44lbs is only about 5 gallons. If its winter and you have a big freezer outdoors thats not hard.
check out this site if want to do some calculations (maybe it will help with your new build):
http://www.3dplumbing.net/ontplumbing/latent_heat.htm
ice 0 to 32 = 16BTU/lb
ice 32 to water = 144BTU/lb
the state change gives most of the cooling capacity.
By the way, I was impressed with your old rig. Yooper even showed me the magazine article (BYO?). I gotta get over and check out a brew day with it.