Simplified Alps Type III were an attempt to produce "fake Alps", i.e. switches that con people into believing that they have real Alps switches. One of the factories producing Alps switches (e.g. Goldstar Alps, or Forward Electronics) made one or more bad batches of switches with a lot of the mould numbering missing (leaving empty circles) and someone got hold of the shells. You can see one of the switches here:
Datadesk Switchboard — the correct internals are present, indicating the switches are legitimate, just badly made.
There would have only been a small supply of these bad shells, so I imagine Simplified Alps Type III was very short-lived. The OP's keyboard looks the right age for genuine blue Alps, and the sliders have the characteristic blue-grey tone, instead of the vivid blue used in the fake Alps sliders. (Only the shells would have been defective and thrown out, so someone like Himake would have had to dye some white sliders blue, hence getting the colour wrong).
Simplified Alps Type III has only been seen once, maybe twice, in a Focus FK-2001.
There is also
alps.tw type OA1 which is a custom batch of switches where the exterior of the shell resembles blue Alps or very early (unbranded) white Alps, but internally is structured to support the Alps clone contact mechanism. There are no other photos of OA1, suggesting that it just had a regular ivory slider, but I do not know. I don't know that the keyboard has ever been seen, and I do not know that it ever went into production;
Hua-Jie AKF Cherry MX mount is another variant, that I do not think ever got made. I have a document from Himake depicting a similar switch (AK-LEN) that they told me was never manufactured; that had the "wings" but, according to the drawing, not the "side panels" of real Alps (where the sides go wider).
And no, I have no reason to believe that blue simplified Alps exists. Blue was long gone by then; it was only made for a few years.