If you're using an older Taylor model #1470 w/cable, you can get a replacement probe from Taylor. Here's the information. 

Parts INFO------
Taylor Model #1470 additional probes are available at the listed price of
$5.00 each. Taylor does not take credit cards or Cod, personal check or
money order will do. Please when ordering please write the part number
(#1470RP) somewhere on the check or money order. Please make out to the

Taylor Precision Products
2220 Entrada del Sol
Las Cruces, NM 88001
Attn: E. Salas