Just to clarify things a bit: A5 is a Integrated Amplifier - means it has volume control.
Regular amps don't - they just amplify by fixed amount.
Given that A5 msrp is 120 of your queens currency
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, 70p for 2nd hand doesn't sound to me like a great deal. It could've been purchased on sale new for 80-100p
Though I don't have personal experience with Cambridge products - I think they are making solid products.
Your Azur 340a is obviously more powerful than A5.
I would recommend to look for second hand Yamaha receivers - they are bulletproof and great value.