I have an old accelerator board used in the PDS slot of an Apple Macintosh SE/30. The board was manufactured around 1994. I want to replace the electrolytic capacitors but I’m not sure how to decode the numbers printed on the caps. Here’s a photo:

As you can see the numbers are:
22
6A
7C6
I could take guess and assume that 22 means 22uF, but what about the voltage spec? Would 6A mean 6.3V? Do any of you know? There’s no logo mark on the cap that I can see to indicate manufacturer.
Capacitor dimensions are:
Diameter = 4.0mm
Height = 5.9mm (including plastic base)
Thank you.