Brake advice needed

[BigChigg]

OK, so I have a '73 FJ40 with 4-wheel disc brakes (great!). The front equipment comes from a late 1980's Toyota truck, not much trouble there.

The rear is of unknown origin (have asked previous owner, no luck). Brake pads are getting thin and need to be replaced. But without knowing what vehicle the calipers came from, I'm dead in the water trying to identify the correct pads. I have pulled the pads and had a look. The axel appears to be original FJ40 to the end and the caliper mounts are bolted on, not welded (that's good). There are some numbers on the single-piston caliper on side toward driveline: 4811 D89. Local auto part stores and internet have come up empty on associating this caliper with a production vehicle. Of course it could be a disc brake conversion kit with custom pads (hope not).

For now, I'm putting it back together with old pads till I figure this out.

So here are my options and questions:

1. Change pads. Can anyone make sense of these caliper numbers?
2. Replace calipers. If I go with a new caliper system, what would you recommend? I'd like one with stock pads from a production vehicle.
3. Do I have any options besides 1 or 2 above

 

[BigChigg]

Here are some photos (if this works)

https://dl.dropboxusercontent.com/u/65489897/FJ40/BackLeftCaliper.png
https://dl.dropboxusercontent.com/u/65489897/FJ40/CaliperNumbers.png
https://dl.dropboxusercontent.com/u/65489897/FJ40/BrakePads.png

 

[edwjmcgrath]

Those look like 1985 Chevy Monte Carlo front pads which are a common application for rear disk conversions.

http://www.autopartswarehouse.com/shop_years/chevrolet-monte-carlo-brake-pad-set-1985.html

I'd take the old pads to your auto parts store and match them up to be certain.

 

[BigChigg]

Think you nailed it Mr. McGrath. Many thanks.