@Louisa1980s
Have you tried using those condoms with gel that slows him down? We use the Durex "mutual pleasure" condoms for this very reason. They have some kind of mild anaesthetic. We also noticed that the Durex ones work well but the Boots don't. Every person is different.
Also, some men last much less without condoms.
You could also try giving him a handjob first (or whatever works for you), then, while he's recovering, ask him to "play" with you (finger, tongue, toys, whatever rocks your boat). Many men tend to last longer the second time, but recovery time varies a lot from person to person. I suspect it increases with age but I don't know for sure.
Another thing you could try is to "train" him with slow teasing and masturbation. E.g. is tie and tease, tease and denial etc anything you could both like?
You could start by first making him come relatively quickly, then slowly increasing the time. So maybe today you make him come in 2 minutes, but in 2 months you make him come in 10. Ask me how I know :)
Of course I get it that these things are hugely subjective, YMMV, not everything is everyone's cup of tea, etc