According to L Costermans "Native trees and shrubs of south-eastern Australia", A. linearifolia has its globular flowerheads in racemes; see the 4 CNM records of A linearifolia. The leaves of the photographed specimen seem to have several veins; the globular flowerheads are on axillary peduncles, either single or in pairs. There are a number of non-local Acacia species which fit these features and which flower in Spring.
I checked all the fine-narrow phyllode-Acacia I could find in CNM but none of them seemed to fit perfectly. According to FloraVictoria, Acacia linearifolia has globular heads, prolific racemes and a prominent midrib with a mucronate tip. the hooked tip is just evident in the photos but no sign of prominent mid-rib.
Jane please check the A linearifolia recorded on CNM, Acacia linearifolia The globular flowerheads are arranged in open or loose racemes, quite different from those shown on your photo.
M, I agree with your proposed id. A cognata (1) and A menzelii (2) are the only other Acacia with similar flower arrangement and thin narrow leaves and tips blunt, oblique or hooked but differ (1) pendulous foliage and thin peduncles and (2) 1 prominent midvein and 2 obscure veins; photo one seems to indicate several veins. W