Have a look at the process involved for each police certificate separately and try to tackle them one at a time as the process can get overwhelming. If you find one that is difficult, put it aside for now and try to sort the others out. You may be able to apply for and get some in a couple of days depending on the proccess.
I know for example that some are really difficult. I used to live in Sichuan, China and I couldn't get it for my application. I sent loads of emails to embassy's in my old home town, sent emails to law firms, visa offices and specific police check consultancies in China and they all confirmed the same thing: i had to physically travel to my old home town to get it done. I was told by one consultancy they could do it for me for a fee starting at $800USD which I laughed at. I was warned by my embassy that the only way to do it was to be there in person. I included all those emails confirming I had to go there and also the one showing how much they wanted to charge. I included evidence of how much it would all cost and said I couldn't get the time off work. All of that together seemed to be enough as I got approved for my PR recently.
7 PCC's will be tough. But as I said, try to tackle it one at a time. Figure out the protocol for each place. In CHina, if I had lived in Beijing or Shanghai, there are companies that can do it for a reasonable price. But as China is not a federation per se, my home town was different.
CIC's website tells you the process they expect you take to get it. If you can't get it through the channel that they suggest you go about getting it, show all the proof that you can't and submit it all together in an organised way.
Make sure to write a good explanation letter also explaining the nature of the job and that you can attest to your good citizenship in each country!
Good luck!