Hoss, $80 seems very high, I paid $60 once, now I have my tank recharged for $20, if I need a fill for a spare tank it's $30. I bought some semen a couple years back and the rep, I can't rememeber who ABS or Genex, charged me $10 for the recharge another Rep charged me $50.... so they seem to be all over the board. The folks that charge me $20 for the recharge is called Airgas, they sell bottled gas, oxygen, CO2, LN2, welding supplies, etc. You may want to see if you can find a welding suppy outfit, or check with a few stud reps for price quotes. I should also say I have a MVE 20/20, I believe it is a 20 liter tank, so figure a recharge at around 6 or 7 liters. Another note is Airgas really does not fill the tank completly, meaning they turn off the LN2 when it starts to spit out of the tank, so it may be down 1/2 leter or so from full. Where as both the reps I have use will just turn down the volume and fill the tank to the top with true liquid and push out the excess with the plunger..... I hope my discreption makes sense.
Hope this helps,
Alan