Before I move off on my morning reads I wanted to add some information.
I read motor needs lubrication.
Most older equipment uses bronze bearings not ball so they need a few drops of oil now and then.
Don't use motor oil.
Its detergent and will likely cause dirt to move and migrate around and could shorten the life of the bushing .( trip to machine shop and new bushing or replace motor if this happens )..
A non detergent oil like this will work
https://www.grainger.com/product/3-IN-ONE-Electric-Motor-Oil-Conventional-3UM48
A non detergent 30 SAE oil will work too.
Steam oil, low speed turbine oils all will work...
Veg oil is not going to work.
I once had a guy bring me a Hobart Potato peeler with 30 years of disgusting veg oil and potato in it.
Just awful to repair, and expensive...
Converting the heater element to 120 is pretty easy.
Just split the heater coil in two and parallel fuse accordingly or use a Self resetting klickson...
It might be worth the trouble to look for a heater from a more modern dryer and see if you can remove the unit parts you have and adapt the newer one.
Your biggest concern is that the coil has to be supported so it will not sag and touch the metal surfaces of the dryer.
Second is all 120 volt heater with a single sided contractor be wired to break the hot and not the neutral.
There are situations where the OEM also wired the heaters single sided and left the other side hot and connected at all times
READ and Consider.
IF the heater coil sags or breaks in the drier and touches the frame of the dryer it may not cause any short that trip breakers of fuses.
It will draw power however if the high side of the coil is not disconnected from the line and the result could be a fire as the coil stays hot and overheats the unit.
Make sure the heater coils are well supported and never left connected to line when the drier is off.
Parts to convert single sided 240 volt driers are easy to get from a just about anyplace no reason to leave it that way
This is really cheap, check your heater rating before buying and be sure its the correct size
https://www.amazon.com/Packard-C230C-Pole-Contactor-Volt/dp/B004YW5CWQ.