Stuart, got the Contax LC-1700 rapid wall charger for mine and the new 1700Ma battery.
The set was Â£89 normally Â£50 each and battery is fully charged in less than 2 hours, i find that after 1 hour mine is charged after normal use. Another tip my Dealer told me was to use the SA-1 adapter from the old TVS it works fine for a more powerful flash I also have a TLA 200 and NO red eye.
Although you will end up spending a few pounds more than the Â£89 already mentioned, you might want to consider getting a Maha charger. These will accept just about any battery you can think of, Li-Ion, NiMH or nicad, camera, camcorder, mobile phone -- you name it. I got one because they're the only economic option for charging the Canon NiMH battery that goes in the booster grip of my EOS-1v. (Canon's charger is extortionately priced at over three hundred quid!) Mine has the ability to do a controlled deep discharge of your batteries to recondition them, and it produces an accurately measured figure for their capacity in mAh while it's about it. They do a slightly cheaper variant that doesn't have this extra feature, but it wasn't in stock when I ordered. Have a look here:
The two units to check out are at the bottom, the MH-C777 and the "Plus" which has the analyze function. The only thing against them for your requirements is that they are quite large with a separate PSU block, although they are still most definitely portable.
Regarding the issue of battery compatibility and the 1500/1700 figures you mention, it's a simple matter of "more is better". The units of measure are not milli&eres, but milli&ere-hours (mAh) and indicate the capacity of the battery. Compatibility is determined by voltage and (in high-drain applications) internal resistance. Your camera will draw the current it needs from your battery, and as long as the battery's internal resistance is not too high, the battery will be able to deliver it without a major voltage drop. Generally, if your device accepts a battery of a certain type (say 6V NiHM) then you should be able to substitute another battery of the same type and voltage without any problems.
Glad to be of help. The charging rate is reasonably quick, but not ultra-fast. Four 2000mAh NiMH AA cells took a few hours (didn't time it, but it was around 3 hours at a rough estimate). A nice feature of the charger is that it goes into a low current top-up mode automatically after the end of the fast charge cycle, so if you leave the cells on there overnight you get a really high capacity charge, more than a simple fast charge could achieve.