WRX Maf problem !

Right, here is the spec: the car is a 96 WRX Impreza Wagon(GF8D, EJ20G), shes got a front mount intercooler, APEXI full exhaust decated,
has no air filter box, instead has normal shitty filter, and Maf has a purple sticker, but she is a Jap Import !!!
And unbeliavebly she is not mapped as far as I got in my conclusions. I only hv it for a few months, bought it from someone who didnt take care of it.

So the problems is that when Im driving(long drive only), she kinda stumble a lot, she even died with me in the middle of the road last night on my way back from Galway.
Me and a friend, Jonh from Clare, who is a member of ISDC, are pretty sure is the Maf thats gone. Easy to fix I believe, just change, but then
comes the mapping which is what probably caused the Maf to go.

But the dilemma here is that in June/July, Im going for major upgrade on my WRX, as the bottom end is starting to knock, so all that will get upgraded,
along with turbo, injectors and etc........ So for now Im only looking for the cheapest solution to keep going until the summer, as I dont want to change
the Maf and hv it broken again, or change the maf and hv to pay for mapping now and when I get the upgrades !!!!

Thanks for any help lads ..... good luck !!!

its possible the MAF may only be dirty, you could try clean the sensor with electrical component cleaner
have you checked the fault codes

I cleaned already and it's still the same.
And the codes were pointing to TPS, MAF and Crank position sensor.