A friend and I recently acquired seven of these onboard welders. These were made when Powermaster (the alternator/starter company) was thinking of offering a new product line. They contracted-out to Mobi-arc, who made these private label units. These welders are brand-new (never used), however they carry no warranty of any kind. The specs on these units are the same as the 200x unit offered by mobi-arc, so I believe they are basically rebranded 200x units. As that is the case, these will likely require modifications to your alternator. You can get these accomplished in various places, and I can help you if necessary. However, the price is just for the welders - and it is $350 shipped in the USA. International shipping available at an increased price. These seven are the only ones that I know of (well, we bought ten but are keeping three), so once they are gone I will never have any others.
The welder is basically an external regulator. Wiring-up the main cables is easy, the only "hard" part is wiring the 10-pin connector. It requires connections made to field + and field - (field - would be a ground to the housing unless using a dual field alternator), Battery or diode trio, Tach out, ignition switch 12v, alternator warning light, battery ground. Your internally regulated alternator will need to be modified to accept these connections. If you are running an externally-regulated unit, you have these connections already. This can be accomplished for $120 which includes shipping back to you in the U.S. (International would be a little more expensive due to the shipping). If you are handy with wiring diagrams/and a soldering iron and are comfortable taking your alternator apart, you can accomplish this on your own. Of course, the welder comes with instructions which explain all of this. Here is a good write-up of what it takes to modify your own alternator:
Again, I am happy to offer a service through mechman for modifying your alternator for $120 including shipping back to you, or I can price you a high-out aftermarket replacement with a two-year warranty - but you are welcome to do it on your own. Obviously, please be confident in your skills before attempting this on your own. A mistake could create a dangerous situation.