Thanks for the question.
While there is no specific Canon addressing your concerns, let me offer my perspective.
The fundamental point of sex is both procreation and unification of the spouses. You must remain open to life, so your ejaculation needs to be during intercourse (even if you consider yourselves beyond child bearing age). The orgasm of the wife is not explicitly demanded at the time of the male climax, it could precede or follow the male climax, but the use of foreign objects is unnatural and borrows pornographic elements, which is not holy.
If you were to manually stimulate your wife to arouse her and prepare her for intercourse, then you could both benefit by the foreplay. I think the artificial aid (sex toy) takes something sacred and makes it profane. If you are having erectile problems, which seem to alleviate when you watch your wife get aroused, the problem seems to be more in your head.
- Have you ever had an addiction to porn?
This could be a consequence of that, if not the normal effect of aging.
The bottom line is that your sex life needs to be a sacred thing, not something that would embarrass or offend God.
He delights in husband and wife renewing their covenant, but not when they treat each other as sex objects.