The Keilidhs, (pronounce the same as ceilidh, a scottish party). Are fairly easy load, 4ohm, and quite sensitive, not needing huge power. The early ones with a mesh tweeter can ring and a bit and be a bit hard/harsh one note. As most early metal dome tweeters. The later 3 bar are much better. All can be updated with the soft dome type from the Ninka/Katan. for about £80.
Most can be had with the Kustone basses, a must. it tightens the bass no end.
The last ones had full veneered front faces, and not grey speckle finish.
For sure a good match is a Linn amp, but an amp with a well designed power supply should work well. Ie the amp that is rigged to give good current and not just a lot of volts to achieve higher power ratings !
Bit surprised by the Quad, guess it is just to warm and laid back amp to get them going.
Old Arcam amps is probably about as "warm" as you want to go. An old delta 290 would be fine. Use to dem that combo.
Another Linn bargain is the Intek. It is a full width, integrated amp. It was Linns answer to the Audiolab 8000a.. but was a hell of a lot more musical and enjoyable to listen to... These seem to fetch around £100.
They were then replaced by the original Majik amp. The power rating is about 50watts, but like all Linn amps they are designed to work down to 4 ohm loads with issue.
They can be driven active, the most common way was a pair of LK100's.
I've had some on the end of 7-8K worth of Linn electronics, they were singing then

!!
TBH, they are far from my favourite Linn speaker, but I know them well enough, to say they are easy to live with, and appeal to many people. Linn must have sold more of these than any other.