James,
I just scanned quickly through my copy, looking for Model 150. It's there but being an early model there is neither an exploded diagram nor a dedicated parts list.
What you find are Lionel's master parts lists, covering all models, by year. In them are line items that apply to the 150. (In other words you have to do a manual search through an entire master list, one line at a time, in order to find the parts that specifically apply to the 150.
However, there are other sources other Greenberg, and the folks responsible for these (ttender.com is one of them) may have gone through the extra trouble of generating a detailed and dedicated 150 parts list from the master list at a more recent point in time.
I can't find any.
So, you may have trouble finding a concise summary of what parts make up a 150. The parts appear to be available, just not summarized concisely.
You've come to the right place though. There are folks in this forum who know the details, even if those details are not written down for convenient access.
Any comments from our experts?
Mike