what to do?

Problems:
- That kind of RAM is no longer sold
- AGP cards are no longer made

You can't really upgrade that PC with 1 of 2 items, the only thing you -can- get to a new PC is that 40GB Harddisk, but the cheapest 500GB Harddisk is about 40 Euro here in Europe...

Just look for a cheap total upgrade:
- Cpu: AMD Phenom II X2 550 Black Edition 3.1Ghz AM3 Socket -> 80 euro/dollar
- Mobo: Asus M4A785TD-V EVO AM3 DDR3 [Integrated Graphics + Sound] -> 90 euro/dollar
- Ram: Kingston ValueRAM KVR1333D3S9 1GB DDR3 -> 30 euro / dollar
- Harddisk: 500GB Seagate Barracuda SATA HD -> 40 euro/dollar

Total: 240 euro / dollar

Cheapest upgrade I could find for you, parts are quite fast, and you can upgrade it a lot more if you want:
- More powerfull AMD AM3 CPU > Anything what's in your budget, but this CPU is already fast enough for maple -by FAR-
- 1GB Ram > 4GB (30 euro per GB)
- External Videocard (PCI-Express) > Anything what's in your budget, just remember, maple isn't GPU dependant, it's all CPU power...

you act as if they no longer exist. i'm sure he can find either of them at a local computer shop or even online.