Upgrading your SIM card

I am an MTN Pay As You Go customer.

I have had my cellphone number for 6 years.

Together, me and my cellphone number have survived three serious relationships, 4 different houses, my best mate's neighbour's psycho-stalker chick (who got my number), and one sociopath. I am rather attached to my cell number.

Cell number is still young at heart, and has plenty of milage left in him. However, the state of cellnumber's body is not too good. He's old and a little outdated. He's a 16k SIM.

Time have moved on, and cellnumber needs a makeover. He needs to upgrade and become a 32k, so that he can compete with all his mates out there as well as giving me access to cellphone banking.

However, MTN want over R100 to give me a new SIM with the same number. I think this is appalling. Their costs are nowhere near R100. I can pick up a 32k SIM for R6 up the road. Only problem is that it won't be the same number.

This is just a plain oportunistic rip-off. I am probably gonna end up getting a new SIM to use exclusively for my banking.

Any suggestions on what I should do, or what we as consumers can do?

i also have the same problem with vodacom, i got a samsung Z500 with a 16k sim card, had the simcard for 5 years now. they wanna charge me just over R100, and they dont even backup the numbers and sms's on ur sim, i had to do that on my own.
come on vodacom, i doubt it cost the company R100 million to write the program that migrates a number to a new sim.