You're doing your body a disservice if you buy salted peanuts.
You need a good blender. Once that happens, bulking on a budget is easy. I used to do at least 3 shakes a day and each time would have 1.5 cups of oats (450 cals) and 1/4 cups of walnuts, almonds, or peanuts (~200 cals). That's 650 easy calories. Throw in a cup or two of skim milk, you're at about 800 calories. Maybe some egg whites or plain yogurt. Add some fruits and veggies, you're at about 900 calories. With 3 shakes, you're at almost 3k calories a day and what I just mentioned doesn't cost a hell of a lot, although walnuts + almonds cost much more than peanuts.
Throw in 2 meals in between shakes that contain calorie dense items like rice and spaghetti, along with the good proteins like chicken + tuna. You're looking at 4-5k calories, no problem. I bulked on a budget for a long time. I also have a thinner frame. I'm down towards a more natural weight of 170, but I used to be around 230.