What kind of side feed injector is this thing?

[STi-zy Wagon]

Here's the injector from my version 4 STI RA.

I have a set of USDM STI 550 side feed's and they look nothing like this... And I need to replace/upgrade these and I don't know what to look for...

Does anyone have any advice?

 

[STi-zy Wagon]

Here's the USDM 550 for reference.

PS. these are for sale

 

[SUBARUDE]

how much?