depends on the engine ?? a few A series have gone from here cheap or for a couple thousand ready to bolt in .... check these for a couple examples :

A14 engine (bare)
+0.040 bore with new pistons and rings at beginning of year. Balanced with light flywheel incl 7/16" UNF flywheel bolts. Cosworth grind cam and reground followers. Oval port head with port work but more HP would be available with upgraded head. Good strong engine with 89 rwp. $650

It's a Datsun A15 engine with a list of engine modifications like,
New Bearings and Seals
11.5:1 Compression
JTS Alloy Head
Race Spec Valve Stem Seals
Double Valve Springs
54/86 Camshaft
Bosch High Rev Alternator
Perfectly Matched Twin Weber Carburettors (No Flat Spots, super Responsive)
Brand New 4 Into 1 Thermal Wrapped Extractors
Brand New High Energy Ignition System Consisting of a Bluebird Series 2 High Energy Electronic Distributor with Bosch HEC 715 Matched Coil, 8.0mm Leads and NGK BP5ES Spark Plugs
Brand New Facet Blue Electronic Fuel Pump into Holley Fuel Pressure Regulator
also in the deal is a reconditioned lancer brake booster ready to fit to a datsun 1200
asking $2700 for the complete engine and brake booster

either of these would 'suprise' your mate but probably won't blow his doors off in a straight line ..... but put it into some windy stuff and let the fun begin