Mackie HD1521 woofer replacement

Hi
We have 2 Mackie HD1521 with defect Woofer in one of them. Since sourcing parts for this model is hard, would it be suitable to replace the woofer with a woofer intended for the Mackie SRM 1550? The spec on the HD1521 is 700 watt RMS, 4 ohm and neodymium magnet, while the SRM1550 has 600 watt RMS, 4 ohm and ferrite magnet.
Or would it better to replace the woofer in both of the speakers with the SRM 1550 woofer?