Heres some pics of the conversion - all parts from Honda Accord mid 80's
First the handbrake lever, this is mounted on a piece of RHS to get the allindment right for a rally car, not needed for road use but you may need to redrill mounting holes in tunnel.
Honda cables - with a bit of work these should hide under the carpet.
The Honda Caliper itself - has "Nissin 9CLP86" written on the top of the casting. It bolts up to the Subaru inner caliper and backing plate. You can see the handbrake return spring on top and the hydrolic (sp) lines on the RHS.
hope this helps