Ray,
The selection of monitors seems quite good, and while the prices appear to be a little higher than in the USA it was not obscenely high (5-25% higher?). I have not paid much attention to the desktop PC's around, but I have seen a lot of available desktops for sale (again, prices are a little higher than in the USA). Peripherals like mice, keyboards, etc., are all easy to find. So unless you have some specialty requirements or need an extremely high-end machine, you could get everything here. The one potential downside to buying a desktop PC here is that some are loaded with pirated versions of Windows, which may make it difficult to install/use some of your own legit Microsoft software.
Assuming you already have your desktop set up and configured the way you like it, probably the best bet for you is to bring your desktop PC unit and buy everything else here. If you have a little space and already have a good LCD monitor, it might be worth bringing that provided you have the box it came in (to help it survive the trip). Depending on the airline, the fee for an extra bag would be cheaper than buying a new monitor. If you have the right size box or suitcase, you can fit both a monitor and plenty of other stuff in one bag.