I happened to find my old (1999) copy of an Orion Blue Book. It says the Reference 2000.3 was made in '97 and were only $330 a pair new. The RS-3A and 3B were made from '82-87, and were $1300-1500 per pair.
Thanks for posting that. However, Infinity's model numbering has grown increasingly confusing (ridiculously so, in fact) over the years. The "RS-3A" speakers in the Blue Book are not bookshelf speakers, but large 3-way, 4-speaker towers. The model number for this Blue Book entry should be shown as "RS-IIIa". I bought a pair of RS-IIIb speakers in 1985 for $1500, and I still have them. They need huge amps (250-300+ wpc) to drive them properly - extremely inefficient.