What tomearm ?

New Jersey is quite a ways from Mesa, AZ. Why not search for a more nearby dealer who would be kind enough to take on this job? I found this list of 10 places, not all of which are suitable but it’s a start, by doing a Firefox search:https://www.yelp.com/search?cflt=hifi&find_loc=Mesa%2C+AZ
Audio is a focal and local world.  One of the stores on this list may be able to recommend a repair person, even if they themselves cannot do the job.

Well I would rather send something like a tonearm across the country to a known high quality tech than take a chance on someone who may or may not know what they are doing. Working on tonearms is kind of like watch repair, very delicate mechanisms involved, not everyone can do a good job.
BillWojo

Enlarging a hole is a very easy proposition. Can be done with a carving knife. I seriously doubt the OP cares what it looks like. He would like to be able to play music immediately with a cheap solution. Do you understand what advance lung cancer means?

Also, we do not know if the old arm can be reassembled or if parts have to be ordered prolonging thing further. The safest thing to do is buy almost any used 9 " working arm and throw it on there.
Here is one, https://www.ebay.com/itm/154319851659?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&...

EVEN better a Project arm for $99!!  https://www.ebay.com/itm/Pro-ject-Carbon-Fiber-Turntable-Tonearm-Black-Project/353424393693?hash=ite...

mijostyn"The safest thing to do is buy almost any used 9 " working arm"
Buying a used tonearm or cartridge is kinda like buying used underwear. Who wants that? There is nothing "safe" in buying some thing as fragile, delicate, and prone to damage as a cartridge or tonearm I know there is a guy here who always recommends cartridges that are 50 years old but he's in the business of selling them so that colours his thinking.