Dylan's first soft toy was a monkey with really long arms and legs and tail - and a squeaker in his belly. I cant remember what brand it is - but it was from our local petshop - and I havent seen them any where else.
All I know is that this toy has lasted him the longest! All other soft toys he's been rough with and needed restictching or the squeakers broken - but this one he's so careful with but still plays with it daily - well he parades round the house with it still in his mouth squeaking it. It was so funny when he was sooo little because the legs were a bit too long and he'd constantly trip over them

I'll keep a look out for it to try find the brand - but another suggestion is that duck mentioned above. My parents springer never had a soft toy until a few months ago (he's now 6) - as this was because their older dog destroyed anything like it - and any new toys were automatically hers. She passed away in March, so got him this duck, and he's such a puppy with it

its also lasted a long time too!
One thing I wouldnt suggest straight away is soft toys with rope limbs - puppy teeth often get stuck in them and they find them easy to destroy unlike thicker grown up dog teeth.
For treats we used coachie looking treats, but they were the pets at home brand. Dylan loved them and when he was tiny, 1/3 of one was a decent sized treat. We also put them in his treat ball too.