Not sure they’re your typical mod styles as they are probably from later in the life of the designer / retailer, but it’s always interesting to see some John Stephen Carnaby Street shirts on eBay.
There are two on from the4 same seller, one described as having purple stripes and in ‘exceptional condition’ with ‘no signs of wear’ and said to be around a 38-inch chest, while the second shirt is lilac in colour and said to be ‘immaculate’. That’s down as a 38-inch too with a slim fitting cut.
Botj come with a copy of the mod fiction book All Or Nothing thrown in for free and both have a starting price (not yet matched) of £19.99. Possibly a good investment for the clothing collector.