Do you have a recliner you can sleep on for awhile? That’s what I did.
Good Luck.

I bought just a very basic wedge from Amazon for about $28. I used it with additional pillows propped here and there to support my rTSR arm or backside.

Sleeping is always difficult for the first couple of months after surgery. I spent enough time in the recliner during the day that I needed to have a true bed to return to for any hope of deeper sleep. Plus our crappy recliner does not push back completely flat and has a tendency to want to pop back to a more upright angle whenever you wiggle your seat, not a restful position. After the first couple of weeks, I removed the immobilizer wrist strap in bed at night so I could lay my arm straight along my thigh. My elbow was still connected to the waist strap, so my shoulder wasn't going to move. I normally never sleep on my back, so it was a challenge to find various side angles that would work.

It was recommended that I use a 45° wedge for bed. I purchased the following as I, too wanted to get a better sleep in bed. This wedge is 3 parts: includes a pillow and 2 different size wedges. I am 6 months post TRS and am using the smaller wedge. Best of luck!