I'd second what Crumpette said about the basic manual avent breast pump. I tried a medela electric one and hated it! (But I know people who liked it.) I found I was best off expressing after the first feed in the morning, but I also needed to do it every day, whether I wanted the milk or not - and dd would only drink it from the bottle if it hadn't been previously frozen. And I could never express very much (though my supply must have been fine as I bf exclusively to 5.5 months when we introduced solids, and bf in total to 20 months). I did find it useful at the weaning stage as I could express enough to mix her porridge with, or mix into purees etc.
On the stretch mark front, I just used coconut based body creams, and have one small stretch mark, which you can only see if you sort of stretch my skin out a bit. I got stretch marks during puberty on hips and thighs (the ones that start of red then fade), but nothing like that with pregnancy, which was nice. I think as the bump got big I forgot it had an underneath, and wasn't so good at rubbing the cream in there - and that's the bit that marked. Must remember this time to pay attention to the underneath!
But, the other thing I wanted to say is that I just never think about the fact I have a stretch mark. It really really doesn't bother me one bit. When I look at it, it's more with interest, and 'oh, that was from dd', and in a funny way I actually like that little reminder that I carried her in my tummy. And to tell the truth, I've felt more confident in and happy with my body since having dd than before, even though I never quite lost the last few pounds.
Anyway, ramble over, better get to bed so I can stay awake for my 7.30pm scan tomorrow...