EV's: 252 HP, 252 Atk, 4 Def
EVs: 252 HP / 44 Atk / 116 Def / 92 SpD
EVs: 252 HP / 252 Atk / 4 SpD
PSA: Remember that Pokemon with high base HP in comparison to their Defense and Special Defense, like Hariyama, benefit much less from HP investment than most others do. For example, barring the use of an Assault Vest, Hariyama's optimal spread for general bulk with max Attack investment is 252 Atk / 124 Def / 132 SpD at Level 50, and 252 Atk / 128 Def / 128 SpD at Level 100.
SilverChiko in the case of the first set you listed, since you're using Assault Vest, and assuming you wanted to keep the Attack EVs at 44 to KO 4 HP Mega Kangaskhan, the optimal spread is 44 HP / 44 Atk / 196 Def / 220 SpD as it also survives an unboosted Talonflame's Brave Bird but survives Sylveon's Hyper Voice with 5.5% additional HP.
252+ Atk Talonflame Brave Bird vs. 252 HP / 116 Def Hariyama: 210-248 (83.6 - 98.8%) -- guaranteed 2HKO
252+ Atk Talonflame Brave Bird vs. 44 HP / 196 Def Hariyama: 188-224 (83.5 - 99.5%) -- guaranteed 2HKO
252+ SpA Choice Specs Pixilate Sylveon Hyper Voice vs. 252 HP / 92 SpD Assault Vest Hariyama: 192-228 (76.4 - 90.8%) -- guaranteed 2HKO
252+ SpA Choice Specs Pixilate Sylveon Hyper Voice vs. 44 HP / 220 SpD Assault Vest Hariyama: 162-192 (72 - 85.3%) -- guaranteed 2HKO
Talonflame only uses Focus Sash 5.2% of the time according to last season's Battle Spot Doubles stats, so it's not particularly relevant,
but the same amount of investment guarantees survival against Adamant Mega Kangaskhan's Double-Edge, which
is relevant given that Hariyama's aiming to counter Mega Kangaskhan, so it's not a bad mark to aim for.
I think I'd personally use a spread with more Attack EVs since investing the minimum amount to KO Kangaskhan implements an element of risk against bulky variants. 172 Atk / 220 Def / 116 SpD, for example, also survives both Talonflame's Brave Bird and Sylveon's Hyper Voice, but additionally OHKOes 164 HP / 228 Atk / 116 Spe Mega Kangaskhan (a popular spread in Japan; outspeeds Jolly Breloom and OHKOes 4 HP Mega Kangaskhan with Low Kick).
44+ Atk Hariyama Close Combat vs. 164 HP / 0 Def Mega Kangaskhan: 182-216 (90.5 - 107.4%) -- 37.5% chance to OHKO
172+ Atk Hariyama Close Combat vs. 164 HP / 0 Def Mega Kangaskhan: 204-240 (101.4 - 119.4%) -- guaranteed OHKO
252+ Atk Talonflame Brave Bird vs. 0 HP / 220 Def Hariyama: 186-218 (84.9 - 99.5%) -- guaranteed 2HKO
252+ SpA Choice Specs Pixilate Sylveon Hyper Voice vs. 0 HP / 116 SpD Assault Vest Hariyama: 186-218 (84.9 - 99.5%) -- guaranteed 2HKO