If you don't mind my asking, I want to make sure I understand what audiophiles are referring to when they talk about 'monitors'.
I use the term in preference to 'bookshelf', which is misleading as to placement and even size. A synonym is 'stand-mounted'. Toddnkaya has clarified things nicely.
There is no reason not to consider actual studio monitors if you can find some in your price range. Some audiophiles find studio gear tends to direct the listener's attention to individual sounds more than to the music as a whole, but there is no shortage of audiophile gear which does the same thing anyway. Enjoy finding out what you like! With your pro experience you are a lap ahead.
I haven't heard either of your sources so can't advise on their relative quality. You have 3 options here. You can keep your sources for now, thus freeing up money for an amp or for a lesser amp plus vinyl. If your present sources have digital outputs, you can defer vinyl in favour of augmenting their performance with an outboard digital converter (DAC) and connecting cable (which must be 1.5 meters long BTW). I myself would include inexpensive antivibration treatment for your CD spinner, plus power conditioning for both it and DAC in the form of an isolation transformer, again inexpensive. Or you can just replace your digital source.
Whatever you do with your source, you can afford to take your time and be sure of the move you make. Deals may slide by, but there will always be others. As a general rule, I prefer to have extra resolution at the source rather than downstream. You can't put information back in later once it's been lost.