Try want ads, gun shows, e-gunparts.com, gun shops
Same choke tube as a 1200 or 1400 pump
No no no
My Mossberg maverick holds seven without the tube plug
From Mossberg's website:"Can I shoot slugs or buckshot through a "smoothbore" field barrel with Accu-Choke™ tubes? (500/505/535/9200/88/930 models) Yes, and with sabots or rifled slugs, the more "open" the choke tube, the better the accuracy ("Improved Cylinder" recommended.) The "full" or "modified" choke tubes are preferred for buckshot loads. Slugs, buckshot and steel shot loads are not recommended for use with an extra full "turkey tube" installed, due to the tube's tight constriction. Do not fire any load without a choke tube installed, doing so will damage the internal choke tube threads. "
Try e-gunparts.com
You will have to experiment to find out.
It is not recommended to shoot slugs with a power pack chock on a JC Higgins model.
I'm not familiar with the Regal designation, but I just bought a 13 year old Mossberg 500C, 20 guage pump, with vent rib and accu-choke(modified tube installed), for $150. It looks like it was never fired.
wiring diagram of electronic choke in tube light
Not unless you have to change the choke tube.
choke is connected in series not parallel.lol
Your rifle is a Mossberg Model 42M, made between 1940 and 1950.