You have the one on hand are Chinese type CRT , may not direct replacement .
From: Ed Breya via Groups.Io <email@example.com>
Sent: Monday, June 11, 2018 10:56 AM
Subject: Re: [TekScopes] OT: AT5005 spectrum analyzer display
The HM5010 manual schematics shows the CRT is D14-364, which googles out to be very common, and Hameg uses it in some of there other products.