This seller has a bunch of these bulbs the seller listed another one and this is the third time he listed another one. The listing is auction format or buy it now you better act fast I've bought the first two he had listed.

http://www.ebay.com/itm/Rare-Vtg-Westinghouse-3-Way-50-100-150-Watt-Soft-Pink-Light-Bulb-IOP-HTF-NOS-/251337777653?pt=US_Light_Bulbs&hash=item3a84e621f5

I just bought one from that seller. Maybe he will have more of them and other types of vintage bulbs.