Thanks to everyone for the information, I wanted to give an update.
I didnt't find any part numbers or ID's on the ignition switch itself but after cleaning around the front of switch, I found a tiny number stamped above the key slot "123243".
Using Peter315's link to the ILCO files, I found this key number 123243 was shown as one of the three Mitsubishi key types but was it listed as "forklift" instead of ignition.
With this ILCO number match, I took AirBiscuit's advice and found a set of 3 keys that were listed as "123243" for $6.99 shipped. They arrived last night and they work fine. The new keys have the same shape as the ILCO 1596 profile but are generic with no numbers.
This gets me out of a bind for now. I will eventually look at replacing the entire switch but needed to get it going for some work this week.
I'm still not certain if this was the original switch but here's some pics of switch and the new keys for reference that may help others in the future.
Thanks again for all the help