I went through this in Feb/March, looking for a set of OEM Denso 23250-46050 blue top 312cc air-assist injectors as part of a fuel upgrade for the coming TRD SC install. Spoke with Martin at MotorWest - a forthright and very knowledgeable dude (Props to Tim!).
He said that he very rarely sees these nowadays and had none in stock. He is; however, adapting other OEM injectors, with various flow rates, having designed CNC T6061 aluminum adapter collars to adapt other model Denso, Bosch or Siemens injectors to fit the 5VZFE. At the time, he was offering:
295cc direct fit
315cc direct fit
350cc electrical harness adapter connectors required (double ended for plug and play installation)
400cc electrical harness adapter connectors required (double ended for plug and play installation)
He said the collars can be made with or without air assist passages. Though the pics below show plain aluminum, I believe he's now black anodizing the collars for corrosion resistance. At the time, cost for a set of Denso 315cc from MotorWest was $220, free shipping.
I ultimately went another route, as I found and took a chance on an eBay set from a '97 SC300 w/120k on it for $115 total. The seller was great - retrieved the parts while I was on hold and confirmed the -46050 p/n stamped on the injectors for me. Quality OE parts at a fair price.
Sent them off to Gordon at Witchhunter for refurbishment at a cost of $150. I'm pleased with the end result.
I'd also found these guys in MN that looked like a valid option - they sell direct or on eBay under silvershot_platinum, currently at a discount. Has anybody purchased from them?
OEM Injectors | Fuel Injector Rebuild Service | CS Performance Fuel Injection
Considered FiveO Motorsport too; but they had no stock of the blue Supra/SC300 injectors at the time.
A posting question: I can't get inline image URLs to appear - I've tried Dropbox & Google Photos links - no dice via Chrome or Firefox. Relegated to posting pics as attachments - all piled up at the end. What am I missing? Thanks!