You may find that half of the problem with his feeding is because of the reflux, you could try positioning him in a more upright position if possible, breastfeeding a refluxer can be a great big pain, but it is possible.

I topped up both my boys with formula from birth, I just did not have enough milk, I know cliche, but it took me longer, I kept on pumping if I would give a bottle, and by three months with both boys I was fully breastfeeding. I am a BF advocate, but I can tell you that if Parker (my refluxer) was my first baby, and I didn't have the hang of it from number one, I wouldn't have succeeded with it.

It is possible to do both.