1970 Sony 2R-31 AM 6 Transistor Radio

[vortalexfan]

Hello everyone, yesterday I picked up at a local antique mall a minty Sony Model 2R-31 AM 6 Transistor pocket radio that still has its original leather carrying case with it that is in mint condition yet and the radio works beautifully yet, and I only gave $10 for it. I was curious as to how these fell in the Sony Pocket radio lineup as far as build quality and how high end they were (how many IF Stages/RF Stages compared to other Sony Pocket radios from the time period, push-pull output vs single ended output, etc.) and how common these were, and how reliable were the capacitors and transistors in these radios?

Any Help would be appreciated.