Marty, I've just pulled the shed apart so I could check my Black Hole for you. Sounds great doesn't it

Anyway that assembly is called a ball gate assembly and yes it is exactly the same as the one on the upper playfield directly to the left of the ball shooter assembly.

I checked my 1987 Gottlieb parts catalogue and there is no part number for the whole assembly, but the part numbers for the individual parts themselves are as follows:

A-20604 Wire Form
A-20293 Link & plunger assembly
A-3232   Spring
A-15409 Coil mounting bracket
A-16570 Coil A16570
A-5065  Coil sleeve
A-18702 Coil & stop bracket
C-20297 Gate Frame
A-20606 Gate
A-20294 Spring

Thats all the parts that make up the assembly except for the screws, washers and circlips but you can copy those from the other assembly to see what you need.

Hope this helps you out.

Chris