If you are in the US, get the harbor freight pump. This is the same pump sold by Lapdist and others as a penis pump.
It has a gauge, it is high quality, it is inexpensive. It sounds like you have all the necessary connectors and tubing already. Here it is. If you can go to your local store. If you need to mail order, do it by phone as the standard shipping offered on the web takes 7 to 14 days.
Harbor Freight Tools – Quality Tools at Discount Prices Since 1977
I learned about this pump in this thread:
Lap pump = harbor freight tools pump
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As to cylinders I have a bostonpump standard design cylinder, which was around $55.00
If you order from them, be aware that they are somewhat slow to ship. However the cylinder is excellent.
I also have a Jim Diamond cylinder I purchased from picturebrite for around $30.00. I have the one with this description:
P124 - Jim Diamond 2 inch cylinder
Picture Brite Retail
Some on thunders have complained about the Jim Diamond cylinder not holding a seal, but mine is fine.