Instead of $150 for a new sump, how about looking for a used sump for $60-$80? DIY would work too but will require time to run to store for supplies and puting it together. In the end, are you really saving yourself that much time and expense with a diy?
Others might disagree with my opinion and that is ok. I am not handy and experienced like DIY King so I rather not attempt to build complex sump.