I dont think that solder iron will be in-stock long as it was discontinued last year...but I've had mine since late 1980's only needed it 2x but got it after I traded my bosch (some of the solder was Toxic to all) swapped out my bosch with 6 tubes of solder for the uti 100 and 200.I'm sure you can...
your 3 x 8 ga is why I have a masters appliance 200 watt butane solder iron.
https://www.amazon.com/Master-Appliance-Ultratorch-Self-Igniting-High-Powered/dp/B000BHQ074