Yes, it does have rod bearings and yes it would be expensive to fix. If that engine truly has a rod knock it will probably be in need of a complete overhaul. A 1997 vehicle probably is not worth doing a engine rebuild. However if the vehicle is in fair to good shape, having a good used engine installed would be the way to go. You can call your local auto wrecking yard for a price, it should be at least half of the cost of a rebuild.
But seriously a knocking as opposed to a clicking would point toward a bad crankshaft bearing.
You need to see if it is up high, which is probably lifter noise, or down low which is a crank or connecting rod bearing. Identify it soon, if it is the bearing waiting will only cause more expensive damage.
Bad bearing or rod
Typically.... Connecting rod bearing / crank bearing. But it could also be piston slap, or flywheel.
A bad connecting rod bearing can do this
A bad rod bearing
If its the engine knockins their is no connection just a quicondense. If the knocking is in the rear could be a cracked rotor or something.
A lower engine knock is usually a bad bearing on the crankshaft. Could be a rod bearing or a main bearing.
it could be the center support bearing in your driveshaft
Worn or loose strut bearing (holder)
Bad bearing? Bad connecting rod?
Bad engine bearing? Piston "slap" Fuel Octane rating too low