i did a search...and what do ya know!

http://www.perth-wrx.com/vb/showthre...ghlight=walbro

http://www.perth-wrx.com/vb/showthre...ghlight=walbro
looks like you can choose from the Walbro GSS342 or the Bosch 044

i havent heard of anyone having problems with walbro pumps, and it seems to be the easiest swap (you can diy) as it is a straight fit.