If you are into psych/garage/freakbeat/exotica compilations you might want to pay these sites a visit. There is a massive collection to peruse and listen to. All the classics seem to be catalogued, although not necessarily the full series for each title but it may allow you to fill any gaps in your collection. They list 1600 titles via their home site or if you prefer their YouTube channel and they are adding more each week. Here are the links to both.
Phew that was a slog and some but I've worked my way through the job lot and here are my reflections on the site. Firstly it's some labour of love and you'd be hard pressed to find a more comprehensive site of this type. They offer a multitude of music genres including freakbeat, mod, psychobilly and exotica to name but a few but 60's garage rock and psych tend to predominate. All the main comp titles are represented including some of the more obscure. The things I like most are that every album is offered as a Youtube video that you can sample in entirety. The videos load up quickly and are easy to skip through with no ads or ad blocker warnings. There is also the option to purchase a download for each title but I found that 99% are available on SS. I also like that they classify each album in the title description so that you know the main genres of music that are represented. They constantly add new titles at a rate of around 4 per day and by signing up you get an email notification of each upload. Alas they don't always offer every volume of a particular series but maybe it's just a matter of time?
What I have to say next is no reflection on the site but rather compilations in general. Unfortunately many that purport to include psychedelic music usually have little or no psych content and comprise mostly of beat, mod and garage rock or obscure 60's pop and rock 'n' roll. Almost all of the really good stuff was comped ages ago on "Pebbles", "Rubble" and the likes and the newer comps are usually scrapping the bottom of the barrel. Many are just rehashes of previously comped stuff with the odd mediocre obscurity thrown in and some snazzy artwork to promote sales. To this end I highly recommend the "Searchin' For Shakes" compilation database that does an excellent job of cross-referencing bands and song titles across a plethora of compilation titles. https://comps.soybomb.com/compsproject/intro.php?&lifilter=4&lispeed=1
Well those are my thoughts, no doubt you will have your own but I must say it's well worth the trawl. I already had 100's of titles but managed to find 50+ that were worthy of adding to my collection, which isn’t bad for a weeks worth of effort and if nothing else it allows you to know which ones to avoid and may save you a few quid.