I know you only have a budget ov 100 pound but if ye not in no big rush I'd save up an invest in a nikon or canon bud if ye wanting to take good action shots an wildlife well worth the money
Most the floor fitters just throw off cuts away as I'm one in the skips supplied by the shops or have bits on there van so if ye out an about just ask themm I'm sure they will give ye some saves buying it