Does it really matter?
But if you really want to know, my best guess for 0177 is November 2001. In the official ETS practice test book (e.g. https://www.physics.ohio-state.edu/unde ... GR0177.pdf
), page 72 gives the percentage of test takers in November 2001 that got each question right. Page 74 also provides a little more detail.
You can probably do the same exercise to get the answer for 0877---I don't have that book on hand though. You might have gotten it in the mail when you registered.
However, it might also be the case that the published practice tests are actually compilations of multiple tests in the same year. I think this might be less likely given the text on page 72 and 74, since that text implies that these questions were all answered in November 2001 by some group of people. That said, this does not rule out the fact that alternate tests in the same month (e.g. the Sunday tests) use different questions and therefore the "practice test" might be a combination of the Saturday and Sunday tests.
In the end though, the variation between your test date this year (or next year) and 0877/0177 will be much larger than the variation between months in 2001 or 2008!!