Did Seiko themselves ever fit 'wrong' (substitute) bracelets to certain 7A38's ?
It documents quite a few sightings of the stainless 7A38-7190 SAA053J fitted with Seiko p/n B1615S bracelets (as more usually found on the stainless 7A38-7270 and 7A38-727A), instead of the conventionally accepted p/n B1405S bracelet.
But that hasn't been the only time the question has reared its head.
Readers may recall a couple of instances in the old forum's 7A38-7180 SAA055J model specific thread, where those watches have been found fitted with another 'wrong' bracelet - Seiko p/n B1127C, normally found on another analogue black chrome coated watch, the 6923-7060 SQ Sports 100, instead of the conventionally accepted p/n B1412D bracelet. Over the years, I've seen a number of 7A38-7180's fitted with a variety of different non-original replacement bracelets. Some indeed were black chrome coated with gold plated ornament bars, but having since checked through my photo folders, the first time I actually saw a p/n B1127C bracelet fitted to a 7A38-7180 was in October 2017, when I posted about it on the first page of the old forum's model specific thread:
The simple reason I dismissed that first instance was that the German eBay seller (the watch's original owner) was also listing a 6923-7060 (correctly fitted with a p/n B1127C bracelet) at the same time !!

Fast forward to the next such example in March 2020. To fully understand the context, it would help if you've read this appropriately titled thread: Poorly cataloged UK auction job lots included a DOZEN 7Axx's ! in the eBay section of the old archived forum. To quickly summarize, Mithra bought two job lots at auction. There were actually rather more than a dozen 7Axx's and one particularly desirable Seiko diver. Amongst them were no less than three 7A38-7180's. One was on the correct original p/n B1412D bracelet, another on a p/n B1127C bracelet and a 'head only'. I was intrigued by the one fitted with 'the wrong bracelet'. Mithra kindly provided this side-by-side comparison shot.
In March, Mithra started selling off a few from this haul, including some 7A38's and 7Txx's. Meanwhile I'd been looking for an answer as to why this watch had been fitted with 'the wrong bracelet'. I suspect from the way the majority had been meticulously labelled, the collection once belonged to a collector, who wasn't averse to tinkering. I concluded:
Mithra knew I was interested in (more intrigued by) the 7A38-7180 fitted with the p/n B1127C bracelet and gave me the opportunity to make him an offer (off eBay), but I don't think we ever actually discussed a price. He subsequently listed the three 7A38-7180's on eBay in May (see page 9 of the model thread), although they were no longer in quite the same configuration. He'd swapped the B1127C bracelet onto another 7A38-7180 head, in worn (rather than NOS condition).
Otherwise I might have bid on it.
To misquote Ian Fleming: "Once is happenstance. Twice is coincidence. The third time, reassessment possibly required.”