Your old pump will typically have had been 1/20hp and 88watt with 3/4" OD barb fittings. Typical Model Numbers: SM-959-NHW-14 thru SM-959-NHW-26. (Note that older models of this circulation pump may also have a motor capacitor mounted on the outside of it).

Brand: Dimension One
Type: Pump
Set Includes: Circulation Pump
Frame Material: High Density Ceramic Bearing Ball, Graphite Impeller
Material: Thermoplastic
Model: 01512-321
MPN: E10-NSHNDNN2W
Item Height: 150 mm
Item Length: 130mm
Item Width: 105mm
Features: Fixed Speed
Country/Region of Manufacture: China
Lining Material: Thermoplastic
Water Type: All Water Types
Manufacturer Warranty: 12 months
Item Weight: 2.000000