Janome makes Janomes, Elnas, and Kenmores
Brother makes Brother, but several Babylocks are exactly the same as their Brother counterparts.
White contracts their stuff out to whomever will make the lowest bid. Singer has also been struggling, certainly not what they used to be.
Do you have a Janome dealer that you're planning to buy from? If so talk to them about warranties ect. A year or more of having your machine taken care of will more than make up for those cost differences.
I have a 7 year old high end Brother and it's amazing. I have an "entry level" Elna (the 2600 - sells for $250 when onsale at my dealer) and it's a so so machine.
Sorry to hear your machine is unhappy. Hopefully you can get things sorted out and taken care of without spending to much and being away from your sewing for long.