1.8 inch is a very strange form factor, so you'll run into problems there. Another problem you're going to have is that your notebook takes ATA drives, while most newer ones will be SATA.
The only place I can find one that should meet your needs is eBay (note: not endorsing this seller or product). Make sure that the connectors of any hard drive you decide to get are the same as the one you currently have.
200gb in 1.8 dont think they exist... a 120 from samsung will set you back 200dollars... if the notebook still worth it to you why not? maybe a little ssd like the samsung 32gb would be better and use a 2.5gb external? the connector is a ZIF connector not regular SATA.