Nice ammeter, jsi. Be sure to bring caps up to voltage slowly to minimize the risk of pegging the meter.
If you want to get an actual leakage tester, don't limit yourself to the Heathkit ones. Many Heathkit devices go for too much money on eBay. It's also a good idea to get one that discharges the cap, either automatically or with a button/lever, prior to removal.
Be sure to check local sources, too. I got a Sprague TO-6 locally for significantly less than they go for on eBay.
If you're comfortable with high voltages (I assume so, since you're going to work on tube stuff), you could make your own tester. Have a look at the schematics in the operating/service manuals for some of the vintage testers.