These are out of stock Australia-wide. The QB035 may be a suitable replacement. The plumbing is very similar, but the discharge is centred, rather than offset.

LX WTC50M Spa Circulation Pump found on imported spas. Note that there are other companies selling the same model, cheaper, but with very low-grade seals. LX is an OEM manufacturer that sells various grades under the exact same model name. This is the up-specced version. 

If unavailable, use this as a replacement.

Details:

• 0.35HP
• Hmax: 3.8m
• Qmax 240 l/min
• 220-240V 50HZ 1a
• P1 0.25kw 250watts
• 1400 r/min
• Ph 1 Class 155(F) 
• IP x5
• cap 7uF
• F/450V S1
• Max Water Temp: 50°C
• Thermally Protected
• APUMCIRWTC