Possibly not what you want to hear, but I would stick with feeding to sleep for now, and give it a go again in a month or so. - If you've been trying to settle him but always end up giving him a BF, then he may be getting mixed messages and think that he has to cry for you to feed him, which it sounds like you don't want him to think. - Feeding to sleep is totally natural anyway, the hormones are designed to send both mother and baby to sleep, so if it works for now, then go with it. Maybe you could try to move away from him sleeping in your arms, by using the pushchair for all his naps for a week or so, and maybe see if you can move to getting him to nap in the pushchair in the house once he's used to this?
FWIW, DD is 9 months and still feeds to sleep too - she also does the searching for the breast when she goes in the cot, sort of looking over her shoulder, mouth open. What I've done is settle into a pattern of her feeds timed just before her naps now, - not a great sleeper and a toddler running around determined to keep his little sister awake have meant my nerves were shot, so in the end I just went with what I knew would work. Some days it's hit and miss if she'll settle in the cot, but I've kept it consistent every day (unless we're out, but then it's now so much a problem anyway), upstairs when she seems sleepy (tricky as the timings change every day!) nappy change, into 0.5 tog gro-bag, BF, then into cot. I keep thinking that eventually she'll start going in more awake, and getting used to settling herself.
One thing that did help is she goes in on her side now that she can roll, she's much happier sleeping like this. If you think the pushchair might work for you, then work out a little pre-nap routine and stick with it. The same with the cot, if you'd rather he nap in the cot, then do the same thing every time, even if it includes feeding to sleep at the end. Being consistent really does help. good luck.