I have a really nice super monster for sale. This is "One of a Kind" monster that Seiko should have made.
Base model was SRP581 with blue bezel and PVD case. The mod I did:

-. SEIKO 6R15D movement (yes, it's D variation and less than 2 year old) ==> day wheel and correct mechanism added to show day function.

-. dial from SZEN006 (a.k.a. white night monster, "impossible" to source nowadays)

-. hour/minute hands from samurai (original Seiko)

-. second hand from SZEN006 (original Seiko)

-. "S" signed, black crown from SRP315 (original Seiko)

It took me almost an year to source all the OEM Seiko parts that I wanted. No aftermarket parts used, of course.

Mechanically, perfect working condition. Everything works as it should.
Keeps time within COSC spec on my wrist.

Cosmetically, there is a small nick on the PVD coating at 5 o'clock position. Very minor but just for full disclosure. Otherwise, near "perfect" condition.
Crystal and bezel no blemishes.

Come with original SRP581 rubber strap with black buckle.

My asking is $435 (Paypal, net to me, please), shipped in CONUS by USPS (tracking).