In the early 1970's, Shure introduced a unidirectional microphone with reduced proximity effect. I think it was the model SM53. But it also had a collection of special accessories. Please provide details on the accessories.It indeed was the model SM53 and its sibling, the model SM54. See the catalog pages attached below as a PDF file.
The SM54 was identical to the SM53 except it had a larger windscreen/pop filter. In 1973, the SM53 had a U.S. retail price of $171.00; the SM54 was $181.20.
There were seven accessories created for the SM53:
A53B: 8.75 inch boom arm assembly; used on movie production and television production booms
A53C: 18 inch vibration isolating cable, XLR female to XLR male; an extremely flexible cloth covered cable
A53E: 20 inch boom extension pipe; used with A53B
A53G: replacement metal grill for SM54; converts the SM53 into the SM54
A53M: air-filled, rubber doughnut, vibration isolation mount
A53WS: two-piece foam windscreen set; smaller foam ring fits over the rear-entry ports near the XLR connector
S53P: low-profile mic stand to utilize the SM53 as a boundary microphone located on a stage apron
By 1985, the SM53 and SM54 were discontinued. The final U.S. retail price for the SM53 was $325; the SM54 was $346.