Best mods for a 04' rm

i need some more top end for my 04' rm but i could use more power evreywhere. I only ride MX and i already have a fmf fatty gold series. I need some suggestions for some mods and i don't have much to spend. I was thinking about a big bore 144 kit but i don't know if i should spend the money because im switching to a 250f in about a year

Thanks- Adrian