Below is the cross-reference for RCA HC and HCT logic I have, with RCA/house numbers.
RCA # 7400 # Comment
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TA11699D HC4024
TA13730 HCT237
TA13747A HCT258
TA11694A HC259
TA11613G HC273
TA11672A HC354
TA11734A HC583
TA11749A HC597
TA13749A HCT597
TA11678A HC02 ? poor label
T11685A HC14
P13685A HCT14 Additional # 520392-W4, on two chips
TA11736A HC21
TA13736A HCT21
TA11724A HC30
TA13724A HCT30
TA13655B HCT73
TA11645A HC123
TA13645A HCT123
P11727A HC125
P13727A HCT125
TA13746A HCT132
TA11729A HC137
TA13729A HCT137
TA13699D HCT4024
TA11702A HC4051
TA13702A HCT4051
TA13705B HCT4066
P11708A HC4094
P13708A HCT4094
TA11742A HC4352
TA11744A HC4510
TA11710A HC4511
TA13710A HCT4511
TA11745A HC4516
TA13745A HCT4516
TA11656C HC173
TA11693C HC221
TA11730A HC273
It seems that TA/P starting designation doesn't have function-relevant meaning. The first two numerical digits seem to indicate whether it's HC (11) or HCT (13) compatible.
These chips seem to be engineering samples or early runs or something. Some of them are marked as engineering samples. Others are in brazed pin/lid ceramic carriers. Here is a picture of one of the small sheets of ICs I have.