...the best form of Sildenafil is troches...

Blue Chew?
https://bluechew.com/

If that is the problem you could always try suppositories.

Have they provided you with or directed you to a rehab routine?
For rehab a cheaper vacuum penis pump will probably suffice. There are plenty on Ebay and Amazon.

with some effort they can be applied to other manufacturers pumps 2 Osbon rings load perfectly on my Encore pump. Some other manufacturers' rings do not. For rings that won't fit two on my Encore, I have used a technique where I use one ring then fold the ears into a pump with a new ring on it. Pum...

If your goal is to use a pump for sex, you should experiment on your own with different rings. I tried different manufacturers and experimented with 1 to 2 rings. Several different types work for me, but 2 Osbons work really well. Some VED's come with their own rings. The Encore pump I use does. For...

I have used many different types of restriction rings with my Encore pump. I use 2 for sex. The type of rings don't seem to matter all that much as far as ejaculation. Sizing seems to be much more important. The restriction needed to maintain a good stiff erection, no matter the ring(s) used, does s...

clitoris is the main way women generally experience sexual pleasures,

The external clitoris is just the visible part of the clitoris.
https://www.welcomed.com/blog/3d-model- ... e-anatomy/

Yes the goal is to get stiff enough for sex The goal then is to successfully pump to a good stiffness then add the proper size and/or number of rings to maintain that stiffy when the vacuum is released. This usually takes a medical grade VED. I use an Encore Deluxe, so I am more familiar with that ...

As bldoink stated, go slow and have patience. A good sense of humor helps.

I "assume" the goal is having sex again?

Was that what you were asking about?

Yes. I have experimented with a few of the cheaper pumps and have always had difficulty sliding the ring off over the pronounced lip without losing the vacuum.