Im looking to get a bag to hold my u lock(10 inches long from top to base and the base is 7 inches across)that i can hook via velco attachment to my frame as my handlebars have all the wiring on them and my water bottle tote but i cant find any bags that will fit it when ive been looking online can anyone help me out?

Edit for clarification: the u lock came with a mount but its crap and it doesn't work for my bike frame and i dont want to carry my 35L backpack in + 20 Celsius weather(looking into under armor undeniable sackpack for this purpose but would prefer a actual bag) and i have no racks for panniers or to mount a bag on it and hanging it on my bars gives my a horrible clanging noise when i turn a corner or push up a hill